Shielding assembly and connecter therefor



'May 24, 1938. T. c. GREEN SHIELDING ASSEMBLY AND CCNNEGTER THEREFORFiled Sept. 14, 1936 INVENTOR Fi g. 5

, BY THOMAS C. GRE'EN fiaw a M ATTORNEY My invention relates to anelectrically conlPatented May 24, 1938 SHIELDING ASSEMBLY AND CONNECTERTHEREFOR Thomas C. Green, United States Marine Corps ApplicationSeptember 14, 1336, Serial No. 100.688

2 Claims. (oi 247-48) (Granted under the act oi. March. 3, 1883, asamended April 30, 1928.; 370 0. G. 757) With the foregoing preliminarydiscussion in tlnuous and eiiicient shielding assembly and to aconnecter forming part thereof for connecting toill) completely encased'by a metallic surface; and.

that the enveloping metallic surface be grounded at-its ends and beelectrically continuous throughout its length. In the case of theenveloping metallic surface associated withthat portion of an aircraftignition circuit extending from the magneto to the ring manifoldfeaturesof design in addition to those previously enumerated must be observed ifan eflicient shielding assembly for this portion of the ignition circuitis to be provided.

The electrically conductive casing element which is associated with themagneto end of the ignition circuit and which forms a part of theshielding assembly extending from the magneto to the ring manifold mustbe divided or sectionalized so as to permit easy disassembly and henceready access to the instrumentalities housed and shielded thereby. It isessential, however. that when the divided casing element is assembledthat the sections thereof fit together as closely as posof the dividedcasingelement will be materially impaired and harmful extraneousmaterial such as. for examole. oil. dirt, or water will have access tothe interior of the casing element with attendant detriment to theinstrumentalities housed therein. Since-the divided casing elementassociated with the magneto end of the ignition circuit and forming partof the shielding assembly extending from the magneto to the ringmanifold is detachably connected with an undivided electricallyconductive casing element it is necessary that the connection thereforprovide electrical continuity between the casing elements as well aselectrical contact between the sections of the divided casing element inconformity with the design requirements previously set forth herein.

viewit is an object of my invention to provide an electricallycontinuous and efficient shielding assembly comprised of detachablyconnected undivided and divided casing elements which when assembled areelectrically continuous and main tain their electrical continuityunimpaired and wherein the sections of the divided casing element whenassembled are in electrical contact.

It is another object of my invention to provide a connecter forconnecting an electrically conductive, undivided cas ng element to anelectricah 1y conductive, divided casing element wherein the juncturebetween the connecter parts is sealed against theconnecter exteriorwhereby electrical continuity through the connecter is insured.

It is another and still further object of my invention to provide aconnecter for connecting an electrically conductive, undivided casingelement to an electrically conductive, divided casing element whereinthe juncture between the connecter parts is maintained by direct andintimate, wedgin'g, metallic contact, the said juncture being sealedagainst the connecter exterior to thus preserve unaltered the resistancethrough the connecter and thereby insure an optimum of shielding effectby theshielding casing elements.

Other objects and many of the attendant advantages of this inventionwill be readily appreciated as the same becomes better understood byreference to the following description when considered in connectionwith the accompanying drawing wherein:

Fig. .1. is an assembled vew in section of one embodiment of myinvention;

Fig. 2 is a view in planof the adjustably connected clamping segmentsadapted to be used with the embodiment of Fig. 1; and

Fig. 3 is an assembled view in section of an alternative embodiment ofmy invention.

My invention seeks to provide an eflicient shielding assembly comprisedof detachably connected undivided and divided, electrically conductivecasing elements which is not only electrically continuous but whoseresistance is preserved substantiallyunaltered, this being accomplishedby maintaining electrical contact between the sections of the dividedcasing element and a direct and intimate metallic contact between anundivided. female and divided male connecter parts formed integrallywith or otherwise sutably secured to the respective undivided anddivided casing elements by causing a wedging action between thecontacting surfaces of the connecter'parts'through the medium of asuitable coupling means. The contact or juncture between the connecterparts occurs within the confines of a compressible, fluid imperviousmeans to thus effectively seal the juncture against the shieldingexterior and hence, against the introduction of any extraneous mattersuch as, for example, oil, gasoline, water or moisture, which would havea tendency to increase the resistance through the shielding assembly orto destroy its electrical continuity. g

The shielding assembly of my invention and the connecter forming a partthereof are intended primarily for use with aircraft ignition circuitsand are so described in their specific applications hereinafter. It isto be emphasized, however, that my shielding assembly and the connecterforming a part thereof are not restricted to the aforementioned use butmaybe used wherever and whenever. an electrically continuous andefficient shielding assembly and connecter are desired, as well as anassembly and connecter whose resistance is to be preserved substantiallyunaltered.

Turning now to the drawing there is .shown a depicted in Fig. 1 thereofan undivided casing clement I detachably connected to a divided casingelement! by means of a connecter identified in general by the numeral 3,the said connecter consisting of a female connecter part 4 integral withthe casing element l, a divided or sectionalized male connecter part 5,a deformable and compressible gasket 6 which serves as a fluidimpcrvious sealing means interposed between the connecter parts and acoupling 1 for maintaining a direct and intimate metallic contactbetween the connecter parts and for causing the connecter parts tocompress the gasket 6, whereby to seal the surface of contact betweenthe connecter parts against the connecter exterior.

The female and male connecter parts 4' and 5 are apertured as shown topermit the passage of ignition cables from one casing element to theother. In addition, the female connecter part 4 is provided with aconical recessed surface 8 with which a corresponding conical surface 9of the divided male connecter part 5 is adapted to contact to therebyinsure electrical continuiiy' through the connecter. While theconnecting sur faces of the male and female connecter parts are shown asconical in shape, I do not desire to be restricted thereto since' otherinclined contact surfaces may be employed within the purview of myinvention and will readily suggest themselves to those skilled in theart, hemi-spherical and pyramidal surfaces being illustrative but notrestrictive of such other inclined surfaces.

The female and male connecter parts 4 and 5 are furthermore providedwith bearing faces l and II, respectively, extending outwardly of theconnecter from adjacent the outermost edges of the conical or inclinedsurfaces 8 and 9, these bearing faces being adapted to abut against thesides of the deformable, fluid impervious gasket 6 interposedtherebetween to compress the same and thereby seal the surfaces ofcontacts 8 and 9 between the connecter parts or members I and againstthe connecter exterior.- The gasket 6 is' preferably although notnecessarily annular in shape and is placed about and supported by theannular projection I! on the female connecter part. This gasket orwasher 6 may be fabricated from synthetic rubber, rubber, special gasketPaper, or any other suitable compressible material so long as thematerial chosen is fluid impervious, will withstand the weather and bereasonably resistant to fluids, such as, for example, gasoline, oil andwater. In order to insure a direct and intimate metallic contact betweenthe contacting surfaces 8 and 9 of the connecter parts and a compressionof the gasket 6, the female and male connecter parts 4 and 5 have beenprovided with inclined surfaces l3 and M respectively which are adaptedto contact with complemental recessed surfaces in a plurality ofadjustably connected clamping segments i5 and I 8, which constituteportions of the coupling I. The recessed surfaces of these coupling orclamping segments are brought into intimate wedging contact with thecomplemental surfaces I3 and ll of the connecter parts by means of thenuts I! and bolts i8, or other suitable means, connecting adjacent endsof the coupling segments together. The coupling 1 in addition to holdingthe contact surfaces 8 and 9 of the connecter parts in intimate anddirect metallic contact, and causing a compression of the gasket 6,serves also to furnish some protection to the sealing gasket 6 and toprovide a secondary, electrically conductive path between the male andfemale parts of the connecter.

The undivided electrically conductive casing element i is shown as anadaptor which is in turn adapted to be connected to the conduit throughwhich the ignition wires or cables are carried to the ring manifold.This adaptor may be in any form necessary for the particularinstallation in question. In some cases it will be merely a straightconnecter fitting; while in others it will have an elbow shape of anyrequired angle. The undivided casing element or adaptor is shown withone outlet at I! but may have any desired number, each of the outletsbeing provided with an electrically continuous connecter for connectingthe adaptor to the conduit leading to the ring manifold. The connecterused for this purpose is preferably that described inmy applicationSerial No, 100,687, filed September 14, 1936. As an alternative mode incompleting the shielding path to the ring manifold I may connect theshielding conduit directly to the divided casing element thus dispensingwith the intervening adaptor.

The divided .casing element identified in gen= eral by the referencecharacter 2 in Fig. 1 is formed in two sections 20 and 2|, which serveas magneto covers. These covers are fabricated by separately stampingeach from sheet metal and then assembling the same with their respectivesections of the divided male connecter part, the assembling beingaccomplished by welding, riveting or a similar process, in order toprovide electrical continuity between the sections of the divided casingelement 2 and those of the divided male connecter part. Normally thedivided casing element will be divided into two halves as shown in Fig.1 of the drawing with their upper ends forming an aperture through whichthe ignition wires or cables have their outlet. It is to be understood,however, that the divided casing element 2 may be divided into anynumber of sections that is desired.

The alternative embodiment shown in Fig. 3 of the drawing is identicalwith that shown in Fig.

' 1, except fordiil'erences in the coupling and the and 24 have beenprovided with a flange 21 and screw threads 28, respectively, which areadapted to engage a complemental flange?! and internal screw threads 28'of a coupling sleeve or nut 29. The screw threads 28 and 28' are shownas being coarse in order to allow for any irregularities of manufacturewithout danger of stripping the threads. It is not essential, however,that these threads be coarse. The coupling sleeve or nut 29 ishexagonally or otherwise shaped to permit the use of a wrench fortightening purposes. This nut or sleeve 29 in addition to holding thecontact surfaces of the connecter parts 24 and 26 in intimate and directmetallic contact, and causing a compression of the gasket 25 serves alsoto furnish some protection to the gasket 25 and to provide a secondaryelectrically conductive path between the female and male parts of theconnecter.

In use the fluid impervious gasket is placed about the annularprojection on the female connecter part and the divided male connecterpart brought into contact with the complemental sur-- face of the femaleconnecter part. As the coupling associated with these connecter parts istightened the conical projection on the male connecter part is wedgedinto the corresponding conical recess of the female connecting part,thus providing direct electrical continuity through the connecter.Simultaneously with the tightening of the coupling the sides of thefluid impervious gasket are compressed between the bearing faces of theconnecter parts, thus sealing within its confines the surfaces ofcontact of the connecter parts against the connecter exterior andproviding fluid-tight integrity against the introduction of extraneousmaterials such as gasoline, oil and moisture. A tightening of thecoupling also forces together the several sections of the dividedconical male connecter parts and those of the divided casing element tothus insure mutual and low resistance electrical contact therebetween.Since there is no crevice or gap between the two halves of the magnetoshielding covers the electrical shielding properties of the dividedcasing element are maintained unimpaired and in addition no extraneousmatter such as, for example, oil, dirt and moisture, can gain access tothe instrumentalities housed therein and shielded thereby. Thepossibility oi interruption in electrical continuity between theundivided and divided casing elements is avoided by reason of theparticular type of connecter employed. Thus I provide an electricallycontinuous and efficient shielding assembly for the purposeshereinbefore described.

According to the provisions of the patent statutes I have set forth theprinciple and mode of operation of my invention and have illustrated anddescribed what I now consider to represent its best embodiments.However, I desire to have it understood that within the scope of theappended claims the invention may be practiced otherwise than asspecifically illustrated and 'dcscribed.

This invention may be manufactured and used by or for the Government ofthe United States of America for governmental purposes without paymentof royalties thereon or therefor.

I claim:

1. An electrically continuous shielding assembly comprising incombination a plurality of electrically conductive casing elements oneof which is undivided and the other of which is divided into a pluralityof sections, a connecter for conmeeting said elements together and forinsuring continuity of passage and electrical continuity thercbetween aswell as electrical contact between the sections of the divided casingelement, said connecter including an apertured, electrically conductivemember electrically continuous with said undivided casing element and inintimate electrical contact with a second apertured, electricallyconductive member which is divided into a plurality of sections equal innumber to those of the divided casing element and electricallycontinuous therewith, means for sealing the area of contact between saidfirst and second mentioned connecter members against the connecterexterior and means for holding said members in engagement at theirsurfaces of contact and for forcing the sections of said divided casingelement as well as those of the divided connecter member into electricalengagement, whereby to provide an electrically continuous and efficientshielding assembly.

2. A connecter for connecting an electrically conductive undivided cablehousing element to an electrically conductive divided instrumentalityhousing element and for insuring electrical continuity and continuity ofpassage therebetween, comprising in combination an apertured,electrically cdnductive member provided with a recessed contact surfaceand a bearing face, a second apertured, electrically conductive, dividedmember provided witha contact surface and a bearing face, the surfacesof contact of said members being in intimate electrical engagement,deformable means interposed between the bearing faces of said membersand adapted to be engaged thereby for sealing the area of contact at thesurfaces of said members against the connecter exterior, and means forholding said members in wedging engagement at the surfaces of contactand. for forcing the sections of the divided memher into electricalcontact as well as for causing the bearing faces to abut against thedeformable means whereby to insure an electrically continuous andprotected juncture of said members.

THOMAS C. GREEN.

